The present invention is with respect to a centrifuge, more specially for centrifuging blood, with at least one vessel for a sample of the substance to be centrifuged and which, when the rotor is put into operation, is turned into a horizontal position by centrifugal force.
In the case of prior art centrifuges, used for medicinal laboratories, the rotor has been so designed that the sample vessels for the substance such as blood to be centrifuged are fixed at an angle of about 45.degree. to the axis of turning of the rotor. In such a position of the vessel full of the substance to be centrifuged, the centrifugal effect is not made best use of, because it is only the vector component lined up with the direction of the sample vessel, that is to say only a part of the full centrifugal force, which is used for the centrifuging operation. For producing a high enough centrifuging effect, the centrifuge has to be run at a high speed. Furthermore, the top face of the substance to be centrifuged, as for example the top face of the blood in the sample vessel, will be at different angles to the axis of turning of the rotor in a way dependent on the speed of turning and, more specially, on turning off the centrifuge in the top, liquid part of the blood, that is to say in the serum or plasma, there will be some flow with the outcome that the serum will be mixed with the blood clot or cake at the serumclot interface. For this reason, the prior art centrifuges do not produce the best possible effect which is desired.
Furthermore, centrifuges have been designed in the prior art in which cups or the like are swingingly joined to the rotor for taking up the vessels filled with the substance to be centrifuged. When the rotor is put into operation, the cups are turned out of a position parallel to the axis of turning into one normal thereto. Although with such a rotor a better centrifuging effect may be produced, the rotor is made very much more complex in design. In fact, such a rotor has to be made up of a large number of separate parts such as turnpins, plain or ball bearings and the like for supporting the swinging cups for the sample vessels so that, in addition to high production costs, much upkeep work is necessary and the centrifuge is likely to get out of order. Furthermore, on centrifuging, it is necessary for not only the vessels with the sample to be centrifuged, but the swinging cups or the like to be accelerated up to the working speed, that is to say there is a large moment of inertia. For this reason, such a prior art centrifuge has to be made very strong in design and generally complex in order to take up the centrifugal forces produced by the relatively high masses.